AMMA-UK WP3 ndash; Convection and dynamics课件.ppt

The observed monsoon (v-wind) is much more irregular. Recent rainfall 精品文档 Chris Taylor, CEH Wallingford Surface temperature (1200 UTC) and boundary layer TKE in the afternoon (around 1500 UTC) 精品文档 WAM dynamics By day, the boundary layer ‘maps’ onto soil moisture By night, airflow responds to pressure gradients 精品文档 WP3 ObjectivesConvection-soil moisture-diurnal WP3.1 To develop validated model case studies of the diurnal cycle of convection in the continental WAM, and over anomalies of soil moisture (with WP1; using OWP1, OWP3 and OWP4 data). WP3.2 To use case studies to quantify the response of the WAM dynamics to Mesoscale Convective Systems (MCSs) (using OWP1,3,4). 精品文档 Mixing ratio – an atmospheric tracer showing nocturnal circulations 精品文档 WP3 Objectives: Transport WP3.3 To quantify the transport properties of dry and moist convective circulations, on the mesoscale and the continental scale, through model case studies and through use of chemical tracers that act as markers of source regions and of air mass ages (with WP4). Within this, to model mixing in the monsoon layer and its implication for the monsoon fluxes (using OWP1,3,4 data). 精品文档 AMMA-UK WP3 – Convection and dynamics Doug Parker Institute for Atmospheric Science School of Earth and Environment University of Leeds 29 November 2004 精品文档 WP3 Objectives To explain the basic dynamics and transport properties of the WAM system, including the diurnal cycle of the boundary layer control on the monsoon, and the response to shallow and deep cumulus convection. 精品文档 Water vapour 17/6/97 Moist convection in the south, dry convection in the north (the Sahara): a ‘natural laboratory’ for tropical continental convection. Monsoon winds African Easterly Jet (AEJ) 600 hPa 精品文档 Shallow cumulus Mixed layer Deep convection 精品文档 1. The analysis of the African Easterly Jet is good ECMWF analyses (Adrian Tompkins; in Thorncroft et al, BAMS 2003): Sahara ITCZ 精品文档 Courtesy Tompkins, ECMWF. 700 hPa zonal winds, averag